The present disclosure relates to a substrate processing apparatus, and more particularly, to a substrate processing apparatus capable of blocking particles falling from a lower portion of a substrate to a surface of a lower substrate.
In general, a substrate processing apparatus is classified into a single wafer type apparatus capable of performing a substrate processing process for one substrate and a batch type apparatus capable of simultaneously performing the substrate processing process for a plurality of substrates. Such a single wafer type substrate processing apparatus has an advantage in that is has a simple structure, but has low productivity. Thus, the batch type substrate processing apparatuses capable of being mass-producing substrates are being widely used.
The typical batch type substrate processing apparatus performs a process by vertically stacking a plurality of substrates. Here, when the substrates are loaded to or unloaded from a substrate boat, particles generated from a lower portion of the substrate or particles generated while loading the substrate in the substrate processing process may fall onto a lower substrate. To resolve this limitation, a method of blocking the particles generated from the lower portion of the substrate through a space division plate is being tried. However, the limitation, in which particles generated from the bottom surface of the space division plate or particles generated during loading fall on the substrate, is still unresolved.
In particular, deposition and etching are repeated in a selective epitaxial growth (SEG) process, in which an insulation layer such as an oxide layer and a nitride layer is formed on a predetermined area of a semiconductor substrate, the predetermined area of the semiconductor substrate is exposed, and, only in the exposed predetermined area of the semiconductor, a homogeneous or heterogeneous semiconductor layer having the same crystalline structure is grown. Due to this, particles caused by a process by-product, which are attached to the bottom surface of the space division plate during a deposition process and falling by being etched from the bottom surface of the space division plate during an etching process cause more severe limitation.